Long-suffering Crown Street Mall retailers have again aired their frustrations about Wollongong City Council's refurbishment works, saying the project "lacks urgency" and is driving them to the brink with noise.

Jim McDonogh, who runs an engraving store, called the Mercury in desperation after more than three hours of ear-piercing jackhammering on Wednesday.

"The noise was just absolutely horrendous and when I rang the council and spoke to the contractors they just said, 'This has to be done'," he said.

"We understand the situation, but for the few businesses in this area at the corner of Church Street there hasn't been any respite, because this area has had vehicle and heavy machinery disruption throughout the whole project."

Further east, Northside Runners owner Karl Hayes has become disgruntled for a very different reason.

He said there had been several days where hardly any contractors were on site.

"The work has picked up this week, and we are seeing workmen and machinery in the site, but up until now there was just one man there most days and it has been like that for weeks," Mr Hayes said.

"It seems like there is just not a sense of urgency from the council for getting this done quickly."

He said he was becoming "petrified" the refurbishment would not be finished before Christmas.

Despite these observations, the council's infrastructure and works director Mike Hyde said the $20 million project was "progressing well" and would meet its October deadline.

He assured Mr McDonogh the loud jackhammering noise would stop "in a day or two", but said more workers or tasks completed at night or early in the morning would cause costs to blow out.

"There's a works program that involved the contractors scheduling a certain number of staff, and if we want the project to be affordable you can't have, for instance, 200 people ready to work at peak and then have 80 of them sitting around doing nothing for the rest of the month," he said.

"If they stick to the current program the contractor has insisted they will finish on time."